Why is vapour pressure low at low temperature?
Answer and explanation
Correct answer: Because molecular kinetic energy is low
At lower temperature, the average kinetic energy of liquid molecules is lower. Consequently, fewer molecules have enough energy to overcome intermolecular attractions and escape through the surface. The equilibrium vapour contains fewer particles and exerts lower pressure. The effect is not caused by a changing name, a smaller container, or vapour becoming heavier.
Frequently asked questions
What is the correct answer to this question?
Because molecular kinetic energy is low
Why is this the correct answer?
At lower temperature, the average kinetic energy of liquid molecules is lower. Consequently, fewer molecules have enough energy to overcome intermolecular attractions and escape through the surface. The equilibrium vapour contains fewer particles and exerts lower pressure. The effect is not caused by a changing name, a smaller container, or vapour becoming heavier.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Equilibrium. Topic: Equilibrium in physical and chemical processes.
